Solution - Long subtraction

0.001

0.001

See steps

Step-by-step explanation

1. Rewrite the numbers from top to bottom, aligned by their place values

Place value	tens	ones	.	tenths	hundredths	thousandths

	2	0	.	4
-	2	0	.	3	9	9
			.

Put zeros in the blank number places:

Place value	tens	ones	.	tenths	hundredths	thousandths

	2	0	.	4	0	0
-	2	0	.	3	9	9
			.

2. Subtract the numbers using long subtraction method

Because the upper digit (0) in the thousandths column is too small to get a positive difference, borrow 1 from the number to the left (40) which becomes (39) and get (10).

Place value	tens	ones	.	tenths	hundredths	thousandths
				3	9	10
	2	0	.	4	0	0
-	2	0	.	3	9	9
			.

Subtract the numbers in the thousandths column from the top number:
10-0-9=1

Place value	tens	ones	.	tenths	hundredths	thousandths
				3	9	10
	2	0	.	4	0	0
-	2	0	.	3	9	9
			.			1

Subtract the numbers in the hundredths column from the top number:
9-9=0

Place value	tens	ones	.	tenths	hundredths	thousandths
				3	9	10
	2	0	.	4	0	0
-	2	0	.	3	9	9
			.		0	1

Subtract the numbers in the tenths column from the top number:
3-3=0

Place value	tens	ones	.	tenths	hundredths	thousandths
				3	9	10
	2	0	.	4	0	0
-	2	0	.	3	9	9
			.	0	0	1

Subtract the numbers in the ones column from the top number:
0-0=0

Place value	tens	ones	.	tenths	hundredths	thousandths
				3	9	10
	2	0	.	4	0	0
-	2	0	.	3	9	9
		0	.	0	0	1

Subtract the numbers in the tens column from the top number:
2-2=0

Place value	tens	ones	.	tenths	hundredths	thousandths
				3	9	10
	2	0	.	4	0	0
-	2	0	.	3	9	9
	0	0	.	0	0	1

The solution is: 0.001

How did we do?

Please leave us feedback.

Why learn this

Terms and topics

Long substraction